A considerable number of structures have been devised to aid the transfer of heat energy between a solid material and a fluid. A few examples, only, of these include heat sinks, radiant heaters, automobile radiators and air-conditioning heat exchangers. Heat sinks are commonly thought of in relation to the cooling of the solid material and comprise an array of fins associated with the solid material. The principle object of such devices has been to increase the surface area of solid material contacting the fluid to thereby increase the transfer of heat energy to the fluid. Of course, it is well known that finned arrays can also be used in heating appliances where the object is to heat a fluid. Automobile radiators are designed to disperse heat from the engine to the atmosphere by transferring heat energy from the coolant to the core of the radiator and then from the core of the radiator to the atmosphere. This latter transfer is again assisted by fins to increase surface area. Similar arrangements are found in a multitude of other applications.
Typically the design of such structures used in the transfer of heat energy between a solid and a fluid has been directed to maximising the surface area made available between the solid and the fluid. Nevertheless, the efficiency of such structures in effecting heat transfer also depends upon the flow of the fluid over the solid material. Many structures have been devised which provide considerable surface area but are not particularly efficient due to the restricted flow of the fluid past the structure. In many cases, the natural flow is supplemented by a forced fluid flow past the heat exchanger.
Nature is recognised as using the most efficient energy transfer systems known to man. Invariably, Nature propagates heat in a turbulent motion. At its most efficient, this turbulence is concentrated into a three dimensional singular vortical motion. The shape of this convectional fluid flow is expressed in equiangular logarithmic spirals, where the ratio of contraction or expansion is approximately 1:0.618, or the celebrated Golden Proportion. An example of this flow structure in a fluid is a tornado. Another example is the flame and smoke pattern arising from a fire storm. Prior technology pays little regard to such natural flow characteristics.
It has been said that nature always follows the path of least resistance. Movement and growth in nature flow in a particular specific, logarithmic geometric progression—that of the three dimensional Golden Proportion or equiangular spiral. The intention of the invention is to induce optimum energy transfer by channelling the fluids into their natural flow tendencies by full or partial adherence to Nature's equiangular, logarithmic, path of movement. The invention capitalises on natural vortical flow geometry.
Vortical structures act as ‘heat pumps’ i.e. they can only exist if there is a temperature differential and vice versa. The invention seeks to exploit the exceptional cooling features of vortices. Part of their effectiveness is that vortex geometry can provide high non turbulent rates of adiabatic expansion i.e. heat can be dumped or acquired in an optimum time and distance.
The simplest, essential and most common form of a vortex is a vortex ring or toroid. (FIGS. 13 and 14).
One of the interesting and exploitable properties of a vortex ring is that is has remarkably low friction and is a rapid and highly energy efficient transporter of fluids and heat.
In order to optimise the cooling efficiency of any radiator, heat exchanger, or heat sink, it is beneficial to establish, maintain, and exploit individual vortex structures. Fluid flow, both internally and externally, may be toroid in shape, Benard cells, the shape of a convection vortex, or a potential vortex. All of the above comply approximately to the three-dimensional Golden Section or equiangular spiral.
An excellent example of this in prior technology is the Ranque-Hilsch tube. (FIG. 13)
Applying the design criteria of the embodiments of this invention, wholly or in part, will improve performance of existing thermal conductor structures.